Lo matshini uqulunqwe sisikhongozeli, izikhonkwane ezixhokonxa iipaddles kunye neenxalenye eziguqukayo; I-screw paddle yenziwa ngokubanzi kwi-1 umaleko okanye i-3 umaleko, i-screw yangaphandle converge yimathiriyeli embindini ngaphambili kumacala amabini, kwaye umaleko wangaphakathi wesikrufu uhambisa imathiriyeli kumacala amabini ukusuka embindini, ukuze yenze ukuxubana kwe-convection. . I-cubage ingenziwa ibe yi-rotundity, ngoko ibhatyi inokudlalwa ngokuphendula kunye nokomisa.